Recent advances in plant stress analysis using chlorophyll a fluorescence

Chlorophyll fluorescence (ChlF), a sensitive, real-time, and nondestructive indicator of photosynthesis, enables noninvasive elucidation of the complex physiological and biochemical processes of plants. It plays a unique and important role in plant research, ecological evaluation, and agriculture. To provide a holistic picture of research on ChlF applications over the past decade, a knowledge map was first conducted, which revealed six major areas of ChlF applications in plant stress evaluation and reduction, including drought stress, temperature stress, salt stress, water stress, toxicity stress, and nitrogen stress. This work then systematically summarized the literature in each of the six areas. Finally, we examined practical application bottlenecks and outlined key challenges and frontiers in future ChlF research.